<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .one{
            color: blue;
        }
        .two{
            color: blueviolet;
        }
    </style>
</head>

<body>
    <div id="app"></div>

    <script src="./src/react.js"></script>
    <script src="./src/react-dom.js"></script>
    <script src="./src/babel.js"></script>

    <script type="text/babel">
        let flag =false;

        let c;
        if (flag == true) {
            c = "one"
        } else {
            c = "two"
        }



        ReactDOM.render(
            <div>
                <h1 style={{ color: 'red', background: "pink" }}>哈哈哈哈</h1>
                <h1 className="one">呵呵呵</h1>
                <h1 className={flag == true ? 'one' : 'two'}>呵呵呵</h1>
                <h1 className={c}>呵呵呵</h1>
            </div>,
            document.getElementById("app")
        )

    </script>
</body>

</html>